Ordnance sighting device.



Patented A rys, 1913.

2 SHEETS-SHEET 1 flliorizey.

B. SVISTOUNOFF.

ORDNANGE SIGHTING DEVICE.

APPLICATION FILED NOV. 4, 1911.

Patented Apr. 8, 1913.

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ORDNANCE SIGHTING DEVICE.

Application filed November 4, 1911.

To all whom it may concern Be it known that I, BORIS SVISTOUNOFF, asubject of the Czar of Russia, and residing at WVoskressenskaia Quai No.80, St. Petersbur Russia, have invented certain new and usefulImprovements in Ordnance Sighting Devices, of which the following is aspecification.

This invention relates to the sighting and range finding devices ofordnance and more particularly to devices of the type known as constantsighting line, in which the sighting line on adjustment of the range isnot moved and is consequently independent of the angle of elevation, indistinction to the previously known independent sighting line which isdisplaced only parallel to itself.

The object of the present invention is to provide an improved deviceadjusting itself automatically to a given range, in which the constantsighting line is retained.

The invention consists in an improved sighting device for ordnance,particularly machine guns and the like, in which after the device hasbeen sighted on a given target the line of sight remains perfectly fixedfor any elevation which the gun may be given.

The invention also consists in a sighting device of the above typecomprising a lever adjustably clamped at its fulcrum end to the framecarriage of the gun and terminating at the other end in a circular boxcarrying the sighting arrangement proper and in which is rotatablymounted on a central spindle an arc member carrying a range scalegraduated to correspond to the elevation angle, the range scale beingmoved by means of a toothed wheel attached thereto and engaging with arack sector fixed on the gun or breech thereof whereby the range isindicated at an inspection opening or index While retaining a constantsighting line.

In using the improved device the optical or sighting device proper isdirected on the given target with a constant sighting line. If thetarget is at a distance greater than can be included by the workingsphere of the constant sighting line the cannon or machine gun must begiven an elevation corresponding to the range by means of the elevatingmechanism, which elevation is automatically indicated on the rangescale, while the sighting line itself remains constant and immovableduring both increase and decrease of the angle of elevation.

Specification of Letters Patent.

Patented Apr. 8, 1913.

Serial No. 658,538.

One constructional form of the improved device is shown by way ofexample in the accompanying drawings in which;

Figure 1 is a side elevation of the elevation indicating device on thebreech of a machine gun. Fig. 2 is an end elevation from the view pointof the gunner, and'Fig. 3 is a section of Fig. 1 on the line AB.

The improved device consists of a round box 1 within which is a centralspindle 3 on which is keyed an arc member 4E carrying a range scale 5which parts can rotate inside the box along with the spindle. The boss 2of the arc member has an extension in the form of a toothed wheel 6which engages with a rack sector 7 screwed on the breech of the machinegun or the body of the cannon. The box 1 is formed on the end of a lever9 fulcrumed on a horizontal cylindric member 10 which is attached insuitable manner to the boss of the tripod or support of the gun. Thelever 9 can be clamped to the boss of the tripod or support of themachine gun by screwing up the split ring 11 by means of a handle 12 anda nut 14 with oblique bearing surfaces. By this clamping device theentire device can be made to form a single Piece with the tripod of thegun and remain in this position independent of the angle of elevationgiven to the gun. The optical or sighting device proper is fitted in agroove 13 on the top of the box 1 so that it remains when trained on thegiven target immovable after clamping the split ring 11.

The lever 9 is formed with recesses and stiffening webs and a cast boss15, as shown in Figs. 1 and 3, to effect saving in weight. The boss 15receives an adjusting screw 16 and is provided with a suitably tappedhole for the same.

The whole device is attached to the right side of the breech of themachine gun and is curved so as not to interfere with the cartridgeband. The lever is fixed in position by the adjusting screw 16 and aslotted sector 17 and receives a limited motion owing to the engagementof the rack sector 7 with the toothed wheel 6 rotating freely on thespindle 3.

The device works in the following manner: The optical or sightingarrangement proper is trained upon the given target, the range scale 4indicating the range at the inspection opening 18 which rangecorresponds to the angle of elevation of the constant sighting device.The split ring 11 is then clamped on the cylindric member 10 by means ofthe handle 12 whereby the device is firmly connected to the framework orcarriage of the gun. The wing nut 16 must be unscrewed to allow themotion of the lever 9 inside the sector 17 If, for example, the targetis more remote than the range corresponding to the constant elevationadjusting device, the gun must be given an angle of elevationcorresponding to the given range. For this purpose the elevating devicemust be actuated whereby the body or the base of. the gun is lowered andthe rack sector 7 attached to the said gun rotates the toothed wheel 6and thus moves the range scale 4 attached to the latter, the devicemeanwhile remaining in unaltered position owing to its being firmlyclamped on the tripod or support of the gun. The range is then indicatedon the range scale at the inspection opening 18.

The displacement of the range scale 4 in the circular box 1 is alwaysproportional to the change in the angle of elevation of the gun and theoptical or sighting arrangement proper, fixed in the groove 13 alongwith the entire device remains fixed for all angles of elevation and isalways directed on the target.

From the above description it is obvious that the principle of theconstant sighting line referred to at the commencement of thedescription has been adhered to. The application of the principle of theconstant or immovable sighting line to elevation adjusting devices isbelieved to be completely new.

A special advantage of the present invention lies in its greatersimplicity compared with the inventions according to British LettersPatent Nos. 14:679/10 and 1129/11 relating to the same type of devices.

The simple and very reliable means for connecting the device to thesupport or tripod of the gun guarantees rapidity of operation.

Having now described my invention what I claim as new and desire tosecure by Letters Patent is In an ordnance sighting device, a leveradjustably clamped at its fulcrum end to a gun part, a circular box atthe other end of the lever supporting the sighting arrangement, acentral spindle in the box, an arc member carrying a range scalerotatably mounted on the spindle, graduations on the range scalecorresponding to the angle of elevation, a toothed wheel attached to thearc member, a rack sector meshing with the BORIS SVISTOUNOFF.

lVitnesses:

H. A. LOVIAGUINE, A. M. AGLITZKY.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. C.

